Energie Cottbus coach Claus-Dieter Wollitz is considering resigning after the fans' behaviour during his side's 3-1 win over Wolfsburg in the DFB-Pokal on Wednesday.
Wollitz, whose second-tier side piled the pressure on Wolfsburg boss Steve McClaren, was incensed by the behaviour of his club's fans after they lit fireworks and flares in the visitors' section of the VW-Arena throughout the game.
"It is no fun at all having to feel ashamed in every away game," he said.
Wollitz and his assistant coach confronted the fans at half time, ordering them to stop disrupting the game. He was clearly angry and, as a result, is not sure whether he wants to remain in charge of the club.
"Our fans are ruining everything. Wherever we go, games are disrupted and you get to a point where you realise that you have had enough.
"I want to work where it is clean."
Cottbus will play Hoffenheim in the next round of the DFB-Pokal next month, although Wollitz may no longer be in charge come that game.
"My contract is up for renewal and I will make a decision by January 3," he added.